more writes: The Zopfli Compression Algorithm is a new open sourced general purpose data compression library that got its name from a Swiss bread recipe. The output generated by Zopfli is typically 3–8% smaller compared to zlib at maximum compression, and we believe that Zopfli represents the state of the art in Deflate-compatible compression. Zopfli is bit-stream compatible with compression used in gzip, Zip, PNG, HTTP requests, and others.